Term | Definition |
Cell Theory | Theory that states that all organisms are made of cells, all cells are produced by other living cells, and the cell is the most basic unit of life. |
Cytoplasm | Jellylike substance inside cells that contains molecules and in some cells organelles |
Organelle | membrane-bound structure that is specialized to perform a distinct process within a cell |
Prokaryotic Cell | cell that does not have a nucleus or other membrane-bound organelles |
Eukaryotic Cell | cell that has a nucleus and other membrane-bound organelles |
Cytoskeleton | Network of proteins, such as microtubules and microfilaments, inside a eukaryotic cell that supports and shapes the cell |
Nucleus | organelle composed of a double membrane that acts as the storehouse for most of a cell's DNA |
Endoplasmic Reticulum | interconnected network of thin, folded membranes that produce, process, and distribute proteins |
Ribosome | organelle that links amino acids together to form proteins |
Golgi Apparatus | stack of flat, membrane-enclosed spaces containing enzymes that process, sort, and deliver proteins |
Vesicle | small organelle that contains and transports materials within the cytoplasm |
Mitochondrion | bean-shaped organelle that supplies energy to the cell and has its own ribosomes and DNA |
Vacuole | organelle that is used to store materials, such as water, food, or enzymes, that are needed by the cell |
Lysosome | organelle that contains enzymes |
Centriole | small cylinder-shaped organelle made of protein tubes arranged in a circle; aids mitosis |
Cell Wall | rigid structure that gives protection, support, and shape to cells in plants, algae, fungi, and bacteria |
Chloroplast | organelle composed of numerous membranes that are used to convert solar energy into chemical energy; contains chlorophyll |
Cell Membrane | double-layer of phospholipids that forms a boundary between a cell and the surrounding environment and controls the passage of materials into and out of a cell |
Phospholipid | molecule that forms a double-layer cell membrane; consists of a glycerol, a phosphate group, and two fatty acids |
Fluid Mosaic Model | model that describes the arrangement and movement of the molecules that make up a cell membrane |
Selective Permeability | condition or quality of allowing some, but not all, materials to cross a barrier or membrane |
Receptor | protein that detects a signal molecule and preforms an action in response |
Passive Transport | movement of molecules across the cell membrane without energy input from the cell |
Diffusion | movement of dissolved molecules in a fluid or gas from a region of higher concentration to a region of lower concentration |
Concentration Gradient | difference in the concentration of a substance from one location to another |
Osmosis | diffusion of water molecules across a semipermeable membrane from an area of higher water concentration to an area of lower water concentration |
Isotonic | solution that has an equal concentration of dissolved particles compared with another solution |
Hypertonic | solution that has a higher concentration of dissolved particles compared with another solution |
Hypotonic | solution that has a lower concentration of dissolved particles compared with another solution |
Facilitated Diffusion | diffusion of molecules assisted by protein channels that pierce a cell membrane |
Active Transport | energy-requiring movement of molecules across a membrane form a region of lower concentration to a region of higher concentration |
Endocytosis | uptake of liquids or large molecules into a cell by inward folding of the cell membrane |
Phagocytosis | uptake of a solid particle into a cell by engulfing the particles |
Exocytosis | release of substances out of a cell by fusion of a vesicle with the membrane |